INDIANAPOLIS (AP) — Indianapolis police have arrested a teenager who investigators believe fired the shots that wounded nine young people during the Indiana Black Expo Summer Celebration.

Police Chief Paul Ciesielski said a surveillance camera caught the weekend shooting on tape, and three eyewitnesses identified the gunman.

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Deputy Chief William Benjamin said detectives arrested the 17-year-old male about 3 p.m. Monday at an apartment complex. Benjamin said the teen’s motive was unclear but was believed to be gang-related.

Benjamin said the teen was being held on preliminary charges including aggravated battery and criminal recklessness.

Marion County Sheriff’s Department spokesman Julio Fernandez didn’t know if the youth had an attorney.